Blister packaging has become increasingly popular over the last decade because of its low cost, its ability to hermetically seal the contained product against foreign matter, and its transparency which permits the product to be displayed to the purchaser.
These blister packages usually consist of a rigid or flexible back board laminated to a clear blister sheet after the product has been placed in its blisters. There may be one or more projections or blisters, and they are formed with a simple mold from a flat sheet.
Blister packaging has been extremely popular in the pharmaceutical industry because it permits a plurality of tablets or pills to be contained in a single blister package having a plurality of blisters on a single backboard. Some of these blister packages are called "push-through" packs that permit the product to be removed from the package by pressing on the blister forcing the pill or product out through a fragile backboard, and others have additional peel off backing adhered to a fragile foil, and in these the peel off back must be removed before the user can remove the product, and these are sometimes referred to as "child resistant" blister packs. In still other types of blister packages it is still necessary to puncture the blister itself in order to remove the product, although these have not found considerable success in pharmaceutical packaging because of the industry's recognition of providing an easy opening container for its market. The reclamation of pills in defective packages in the pharmaceutical industry is important not only to repackage and resell the product, but also to minimize hazardous waste if the damaged or defective packaging was discarded.
FDA requirements dictate that blister package machinery in the pharmaceutical industry be placed and operated in individual contamination-free rooms. Not so infrequently, these blister packaging machines either load the pills in the blister improperly or damage the blister packaging in some way rendering it unsaleable. Also by regulation, these defective packages must be reopened in the same contamination-free room housing the negligent blister packaging machine, and prior to the advent of de-blistering machines, this was done by a team of sterilized workers that moved from one packaging room to another in an effort to keep up with this monumental task of manually removing product from blister packages.
While there have been several de-blistering machines designed that have obtained some degree of commercial success, they are very costly and since one machine is required for each packaging room in a pharmaceutical house, and because they are not capable of opening all types of blister packages, many in the industry have chosen to stay with their manual human de-blistering teams.
One commercially available maching, manufactured by Sepha Products of Belfast, Ireland, has been devised for the push-through packages and for the peelable and child-resistant packages, but which require the peelable backing to be pulled away prior to insertion into the machine. The heart of this machine is a pair of mating rotating rollers with one of the rollers having one or more annular recesses therein for receiving the blisters and squeezing the blisters as the package goes between the rollers forcing the product through the back board.
Except for certain feeding problems, the Sepha machine is suitable for the press-out or push-through blister-type packages, but it is incapable of opening other types of blister packages.
Another somewhat more complicated machine has been devised for cutting C-shaped slots in the peelable back packaging, but this machine is quite complicated because it requires the step of cutting slots through the back board and then pressing the blister from the other side forcing the product through the slot into a collection tray. This machine is not only complex but expensive because special mandrels for pressing the blisters and special mandrels for cutting the C-shaped slots must be provided for each packaging configuration making this machine an extremely costly one.
Other objects and advantages of the present invention will appear more clearly from the following detailed description.